What type of food does grems grow best at?

Grems, which are often fictional or whimsical creatures in various stories, don't have specific food preferences tied to real-world Biology. However, if we consider them in a fantasy context, they might thrive on a diet rich in magical or enchanted foods, such as glowing fruits, sparkling herbs, or sweet nectar. These foods could provide them with the energy and nutrients needed to flourish in their imaginative environments. Ultimately, the specific type of food would depend on the lore surrounding grems in a given narrative.